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<FONT color="green">001</FONT>    package org.codemonkey.swiftsocketclient;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import java.io.BufferedReader;<a name="line.3"></a>
<FONT color="green">004</FONT>    import java.io.ByteArrayInputStream;<a name="line.4"></a>
<FONT color="green">005</FONT>    import java.io.IOException;<a name="line.5"></a>
<FONT color="green">006</FONT>    import java.io.InputStreamReader;<a name="line.6"></a>
<FONT color="green">007</FONT>    import java.io.PrintWriter;<a name="line.7"></a>
<FONT color="green">008</FONT>    import java.net.DatagramPacket;<a name="line.8"></a>
<FONT color="green">009</FONT>    import java.net.DatagramSocket;<a name="line.9"></a>
<FONT color="green">010</FONT>    import java.net.InetAddress;<a name="line.10"></a>
<FONT color="green">011</FONT>    import java.net.Socket;<a name="line.11"></a>
<FONT color="green">012</FONT>    import java.net.SocketAddress;<a name="line.12"></a>
<FONT color="green">013</FONT>    import java.util.LinkedList;<a name="line.13"></a>
<FONT color="green">014</FONT>    <a name="line.14"></a>
<FONT color="green">015</FONT>    import org.apache.log4j.Logger;<a name="line.15"></a>
<FONT color="green">016</FONT>    <a name="line.16"></a>
<FONT color="green">017</FONT>    /**<a name="line.17"></a>
<FONT color="green">018</FONT>     * Abstraction of the server socket. Acts as a wrapper for {@link Socket} and {@link DatagramSocket} to provide uniform behavior.<a name="line.18"></a>
<FONT color="green">019</FONT>     * <a name="line.19"></a>
<FONT color="green">020</FONT>     * @author Benny Bottema<a name="line.20"></a>
<FONT color="green">021</FONT>     * @see ServerEndpointUDP#handleDatagramPacket(DatagramPacket)<a name="line.21"></a>
<FONT color="green">022</FONT>     * @since 1.0<a name="line.22"></a>
<FONT color="green">023</FONT>     */<a name="line.23"></a>
<FONT color="green">024</FONT>    abstract class ServerEndpoint {<a name="line.24"></a>
<FONT color="green">025</FONT>            /**<a name="line.25"></a>
<FONT color="green">026</FONT>             * Calls the close method on the embedded socket, or in case of UDP, nothing happens.<a name="line.26"></a>
<FONT color="green">027</FONT>             * <a name="line.27"></a>
<FONT color="green">028</FONT>             * @throws IOException Thrown by {@link ServerEndpointTCP#close()}<a name="line.28"></a>
<FONT color="green">029</FONT>             */<a name="line.29"></a>
<FONT color="green">030</FONT>            abstract void close()<a name="line.30"></a>
<FONT color="green">031</FONT>                            throws IOException;<a name="line.31"></a>
<FONT color="green">032</FONT>    <a name="line.32"></a>
<FONT color="green">033</FONT>            abstract InetAddress getInetAddress();<a name="line.33"></a>
<FONT color="green">034</FONT>    <a name="line.34"></a>
<FONT color="green">035</FONT>            abstract void send(String message)<a name="line.35"></a>
<FONT color="green">036</FONT>                            throws IOException;<a name="line.36"></a>
<FONT color="green">037</FONT>    <a name="line.37"></a>
<FONT color="green">038</FONT>            abstract String readLine()<a name="line.38"></a>
<FONT color="green">039</FONT>                            throws IOException;<a name="line.39"></a>
<FONT color="green">040</FONT>    <a name="line.40"></a>
<FONT color="green">041</FONT>            abstract void read()<a name="line.41"></a>
<FONT color="green">042</FONT>                            throws IOException;<a name="line.42"></a>
<FONT color="green">043</FONT>    }<a name="line.43"></a>
<FONT color="green">044</FONT>    <a name="line.44"></a>
<FONT color="green">045</FONT>    /**<a name="line.45"></a>
<FONT color="green">046</FONT>     * Simply delegates all calls to the {@link Socket}. This is because the {@link ServerEndpointUDP} is modeled after the TCP version.<a name="line.46"></a>
<FONT color="green">047</FONT>     * <a name="line.47"></a>
<FONT color="green">048</FONT>     * @author Benny Bottema<a name="line.48"></a>
<FONT color="green">049</FONT>     * @since 1.0<a name="line.49"></a>
<FONT color="green">050</FONT>     */<a name="line.50"></a>
<FONT color="green">051</FONT>    class ServerEndpointTCP extends ServerEndpoint {<a name="line.51"></a>
<FONT color="green">052</FONT>    <a name="line.52"></a>
<FONT color="green">053</FONT>            private final Socket socket;<a name="line.53"></a>
<FONT color="green">054</FONT>    <a name="line.54"></a>
<FONT color="green">055</FONT>            /**<a name="line.55"></a>
<FONT color="green">056</FONT>             * The input stream from the server on which we're waiting for data. Data is being read with {@link BufferedReader#readLine()}, so<a name="line.56"></a>
<FONT color="green">057</FONT>             * incoming messages need to end with a newline character '\n'. In addition, to work with Flex clients, an additional NULL character<a name="line.57"></a>
<FONT color="green">058</FONT>             * '\0' needs to be added.<a name="line.58"></a>
<FONT color="green">059</FONT>             */<a name="line.59"></a>
<FONT color="green">060</FONT>            private final BufferedReader reader;<a name="line.60"></a>
<FONT color="green">061</FONT>    <a name="line.61"></a>
<FONT color="green">062</FONT>            /**<a name="line.62"></a>
<FONT color="green">063</FONT>             * Creates a {@link BufferedReader} for the socket's input stream.<a name="line.63"></a>
<FONT color="green">064</FONT>             * <a name="line.64"></a>
<FONT color="green">065</FONT>             * @param socket The open socket on which to listen for TCP messages.<a name="line.65"></a>
<FONT color="green">066</FONT>             * @throws IOException Thrown by {@link Socket#getInputStream()}.<a name="line.66"></a>
<FONT color="green">067</FONT>             */<a name="line.67"></a>
<FONT color="green">068</FONT>            public ServerEndpointTCP(final Socket socket)<a name="line.68"></a>
<FONT color="green">069</FONT>                            throws IOException {<a name="line.69"></a>
<FONT color="green">070</FONT>                    this.socket = socket;<a name="line.70"></a>
<FONT color="green">071</FONT>                    reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));<a name="line.71"></a>
<FONT color="green">072</FONT>            }<a name="line.72"></a>
<FONT color="green">073</FONT>    <a name="line.73"></a>
<FONT color="green">074</FONT>            /**<a name="line.74"></a>
<FONT color="green">075</FONT>             * Calls {@link Socket#close()}.<a name="line.75"></a>
<FONT color="green">076</FONT>             */<a name="line.76"></a>
<FONT color="green">077</FONT>            @Override<a name="line.77"></a>
<FONT color="green">078</FONT>            void close()<a name="line.78"></a>
<FONT color="green">079</FONT>                            throws IOException {<a name="line.79"></a>
<FONT color="green">080</FONT>                    socket.close();<a name="line.80"></a>
<FONT color="green">081</FONT>            }<a name="line.81"></a>
<FONT color="green">082</FONT>    <a name="line.82"></a>
<FONT color="green">083</FONT>            /**<a name="line.83"></a>
<FONT color="green">084</FONT>             * @return {@link Socket#getInetAddress()}.<a name="line.84"></a>
<FONT color="green">085</FONT>             */<a name="line.85"></a>
<FONT color="green">086</FONT>            @Override<a name="line.86"></a>
<FONT color="green">087</FONT>            InetAddress getInetAddress() {<a name="line.87"></a>
<FONT color="green">088</FONT>                    return socket.getInetAddress();<a name="line.88"></a>
<FONT color="green">089</FONT>            }<a name="line.89"></a>
<FONT color="green">090</FONT>    <a name="line.90"></a>
<FONT color="green">091</FONT>            /**<a name="line.91"></a>
<FONT color="green">092</FONT>             * Writes message to {@link Socket#getOutputStream()} using a {@link PrintWriter}.<a name="line.92"></a>
<FONT color="green">093</FONT>             */<a name="line.93"></a>
<FONT color="green">094</FONT>            @Override<a name="line.94"></a>
<FONT color="green">095</FONT>            void send(final String message)<a name="line.95"></a>
<FONT color="green">096</FONT>                            throws IOException {<a name="line.96"></a>
<FONT color="green">097</FONT>                    try {<a name="line.97"></a>
<FONT color="green">098</FONT>                            final PrintWriter out = new PrintWriter(socket.getOutputStream(), true);<a name="line.98"></a>
<FONT color="green">099</FONT>                            out.write(message);<a name="line.99"></a>
<FONT color="green">100</FONT>                            out.flush();<a name="line.100"></a>
<FONT color="green">101</FONT>                    } catch (final IOException e) {<a name="line.101"></a>
<FONT color="green">102</FONT>                            Logger.getLogger(ServerEndpoint.class).error("outputstream could not be obtained (tried to use dropped connection perhaps?)");<a name="line.102"></a>
<FONT color="green">103</FONT>                            throw e;<a name="line.103"></a>
<FONT color="green">104</FONT>                    }<a name="line.104"></a>
<FONT color="green">105</FONT>            }<a name="line.105"></a>
<FONT color="green">106</FONT>    <a name="line.106"></a>
<FONT color="green">107</FONT>            /**<a name="line.107"></a>
<FONT color="green">108</FONT>             * @return Data received from the socket, by calling &lt;code&gt;{@link #reader}.readLine()&lt;/code&gt;.<a name="line.108"></a>
<FONT color="green">109</FONT>             */<a name="line.109"></a>
<FONT color="green">110</FONT>            @Override<a name="line.110"></a>
<FONT color="green">111</FONT>            String readLine()<a name="line.111"></a>
<FONT color="green">112</FONT>                            throws IOException {<a name="line.112"></a>
<FONT color="green">113</FONT>                    return reader.readLine();<a name="line.113"></a>
<FONT color="green">114</FONT>            }<a name="line.114"></a>
<FONT color="green">115</FONT>    <a name="line.115"></a>
<FONT color="green">116</FONT>            /**<a name="line.116"></a>
<FONT color="green">117</FONT>             * Calls &lt;code&gt;{@link #reader}.read()&lt;/code&gt;<a name="line.117"></a>
<FONT color="green">118</FONT>             */<a name="line.118"></a>
<FONT color="green">119</FONT>            @Override<a name="line.119"></a>
<FONT color="green">120</FONT>            void read()<a name="line.120"></a>
<FONT color="green">121</FONT>                            throws IOException {<a name="line.121"></a>
<FONT color="green">122</FONT>                    reader.read();<a name="line.122"></a>
<FONT color="green">123</FONT>            }<a name="line.123"></a>
<FONT color="green">124</FONT>    }<a name="line.124"></a>
<FONT color="green">125</FONT>    <a name="line.125"></a>
<FONT color="green">126</FONT>    /**<a name="line.126"></a>
<FONT color="green">127</FONT>     * Server endpoint that handles UDP traffic and maintains a list of known and new datagram messages.<a name="line.127"></a>
<FONT color="green">128</FONT>     * <a name="line.128"></a>
<FONT color="green">129</FONT>     * @author Benny Bottema<a name="line.129"></a>
<FONT color="green">130</FONT>     * @see ServerEndpointUDP#handleDatagramPacket(DatagramPacket)<a name="line.130"></a>
<FONT color="green">131</FONT>     * @since 1.0<a name="line.131"></a>
<FONT color="green">132</FONT>     */<a name="line.132"></a>
<FONT color="green">133</FONT>    class ServerEndpointUDP extends ServerEndpoint {<a name="line.133"></a>
<FONT color="green">134</FONT>    <a name="line.134"></a>
<FONT color="green">135</FONT>            private final DatagramSocket datagramSocket;<a name="line.135"></a>
<FONT color="green">136</FONT>            private final LinkedList&lt;DatagramPacket&gt; queue;<a name="line.136"></a>
<FONT color="green">137</FONT>            private final InetAddress serverInetAddress;<a name="line.137"></a>
<FONT color="green">138</FONT>            private final SocketAddress serverSocketAddress;<a name="line.138"></a>
<FONT color="green">139</FONT>    <a name="line.139"></a>
<FONT color="green">140</FONT>            /**<a name="line.140"></a>
<FONT color="green">141</FONT>             * Constructor; initializes handshake by requesting an acknowledgment command to a handshake connection request.<a name="line.141"></a>
<FONT color="green">142</FONT>             * <a name="line.142"></a>
<FONT color="green">143</FONT>             * @param datagramSocket The {@link DatagramSocket} to send messages to the server with.<a name="line.143"></a>
<FONT color="green">144</FONT>             * @param inetAddress The host address of the server.<a name="line.144"></a>
<FONT color="green">145</FONT>             * @param socketAddress The host and address and port of the server.<a name="line.145"></a>
<FONT color="green">146</FONT>             */<a name="line.146"></a>
<FONT color="green">147</FONT>            public ServerEndpointUDP(final DatagramSocket datagramSocket, final InetAddress inetAddress, final SocketAddress socketAddress) {<a name="line.147"></a>
<FONT color="green">148</FONT>                    this.datagramSocket = datagramSocket;<a name="line.148"></a>
<FONT color="green">149</FONT>                    serverInetAddress = inetAddress;<a name="line.149"></a>
<FONT color="green">150</FONT>                    serverSocketAddress = socketAddress;<a name="line.150"></a>
<FONT color="green">151</FONT>                    queue = new LinkedList&lt;DatagramPacket&gt;();<a name="line.151"></a>
<FONT color="green">152</FONT>            }<a name="line.152"></a>
<FONT color="green">153</FONT>    <a name="line.153"></a>
<FONT color="green">154</FONT>            /**<a name="line.154"></a>
<FONT color="green">155</FONT>             * Does nothing, only useful for TCP socket.<a name="line.155"></a>
<FONT color="green">156</FONT>             */<a name="line.156"></a>
<FONT color="green">157</FONT>            @Override<a name="line.157"></a>
<FONT color="green">158</FONT>            void close()<a name="line.158"></a>
<FONT color="green">159</FONT>                            throws IOException {<a name="line.159"></a>
<FONT color="green">160</FONT>                    //<a name="line.160"></a>
<FONT color="green">161</FONT>            }<a name="line.161"></a>
<FONT color="green">162</FONT>    <a name="line.162"></a>
<FONT color="green">163</FONT>            /**<a name="line.163"></a>
<FONT color="green">164</FONT>             * Returns the server's {@link InetAddress} for logging purposes. In case of UDP {@link SocketAddress} is actually used to identify and<a name="line.164"></a>
<FONT color="green">165</FONT>             * communicate with the server.<a name="line.165"></a>
<FONT color="green">166</FONT>             */<a name="line.166"></a>
<FONT color="green">167</FONT>            @Override<a name="line.167"></a>
<FONT color="green">168</FONT>            InetAddress getInetAddress() {<a name="line.168"></a>
<FONT color="green">169</FONT>                    return serverInetAddress;<a name="line.169"></a>
<FONT color="green">170</FONT>            }<a name="line.170"></a>
<FONT color="green">171</FONT>    <a name="line.171"></a>
<FONT color="green">172</FONT>            /**<a name="line.172"></a>
<FONT color="green">173</FONT>             * Sends a message in the form of a {@link DatagramPacket}, using {@link DatagramSocket#send(DatagramPacket)}.<a name="line.173"></a>
<FONT color="green">174</FONT>             */<a name="line.174"></a>
<FONT color="green">175</FONT>            @Override<a name="line.175"></a>
<FONT color="green">176</FONT>            void send(final String message)<a name="line.176"></a>
<FONT color="green">177</FONT>                            throws IOException {<a name="line.177"></a>
<FONT color="green">178</FONT>                    final DatagramPacket packet = new DatagramPacket(message.getBytes(), message.length(), serverSocketAddress);<a name="line.178"></a>
<FONT color="green">179</FONT>                    datagramSocket.send(packet);<a name="line.179"></a>
<FONT color="green">180</FONT>            }<a name="line.180"></a>
<FONT color="green">181</FONT>    <a name="line.181"></a>
<FONT color="green">182</FONT>            /**<a name="line.182"></a>
<FONT color="green">183</FONT>             * Adds a datagram packet to the {@link #queue} to be processed, which is done by calling {@link #readLine()}. This is so that it mimics<a name="line.183"></a>
<FONT color="green">184</FONT>             * how TCP messages are read, molded into a uniform abstraction ({@link ServerEndpoint}).<a name="line.184"></a>
<FONT color="green">185</FONT>             * &lt;p&gt;<a name="line.185"></a>
<FONT color="green">186</FONT>             * The difference between TCP and UDP is that UDP messages are pushed, by TCP messages can be pulled by the system. And so we need to<a name="line.186"></a>
<FONT color="green">187</FONT>             * cache (or 'queue') the UDP messages until they are pulled by the client the same way TCP messages are being pulled.<a name="line.187"></a>
<FONT color="green">188</FONT>             * <a name="line.188"></a>
<FONT color="green">189</FONT>             * @param datagramPacket The {@link DatagramPacket} to add to the queue waiting for {@link #readLine()} calls the same way a TCP<a name="line.189"></a>
<FONT color="green">190</FONT>             *            messages are retrieved by the client.<a name="line.190"></a>
<FONT color="green">191</FONT>             */<a name="line.191"></a>
<FONT color="green">192</FONT>            public void handleDatagramPacket(final DatagramPacket datagramPacket) {<a name="line.192"></a>
<FONT color="green">193</FONT>                    queue.add(datagramPacket);<a name="line.193"></a>
<FONT color="green">194</FONT>            }<a name="line.194"></a>
<FONT color="green">195</FONT>    <a name="line.195"></a>
<FONT color="green">196</FONT>            /**<a name="line.196"></a>
<FONT color="green">197</FONT>             * Returns a String line from next {@link DatagramPacket} in the {@link #queue}. This is done by using a {@link BufferedReader} to read<a name="line.197"></a>
<FONT color="green">198</FONT>             * {@link DatagramPacket#getData()}. If there are no datagram packets to convert to a string line, this method blocks until a datagram<a name="line.198"></a>
<FONT color="green">199</FONT>             * packet is received or the socket has been closed.<a name="line.199"></a>
<FONT color="green">200</FONT>             */<a name="line.200"></a>
<FONT color="green">201</FONT>            @Override<a name="line.201"></a>
<FONT color="green">202</FONT>            String readLine()<a name="line.202"></a>
<FONT color="green">203</FONT>                            throws IOException {<a name="line.203"></a>
<FONT color="green">204</FONT>                    while (!datagramSocket.isClosed()) {<a name="line.204"></a>
<FONT color="green">205</FONT>                            if (queue.size() &gt; 0) {<a name="line.205"></a>
<FONT color="green">206</FONT>                                    final DatagramPacket datagram = queue.removeFirst();<a name="line.206"></a>
<FONT color="green">207</FONT>                                    final BufferedReader bufferedReader = new BufferedReader(<a name="line.207"></a>
<FONT color="green">208</FONT>                                                    new InputStreamReader(new ByteArrayInputStream(datagram.getData())));<a name="line.208"></a>
<FONT color="green">209</FONT>                                    return bufferedReader.readLine();<a name="line.209"></a>
<FONT color="green">210</FONT>                            } else {<a name="line.210"></a>
<FONT color="green">211</FONT>                                    ServerUtil.defaultSleep();<a name="line.211"></a>
<FONT color="green">212</FONT>                            }<a name="line.212"></a>
<FONT color="green">213</FONT>                    }<a name="line.213"></a>
<FONT color="green">214</FONT>                    // socket.close() will be called when the SwiftSocketServer is stopping,<a name="line.214"></a>
<FONT color="green">215</FONT>                    // returning null won't cause NullPointerException in that case<a name="line.215"></a>
<FONT color="green">216</FONT>                    return null;<a name="line.216"></a>
<FONT color="green">217</FONT>            }<a name="line.217"></a>
<FONT color="green">218</FONT>    <a name="line.218"></a>
<FONT color="green">219</FONT>            @Override<a name="line.219"></a>
<FONT color="green">220</FONT>            void read()<a name="line.220"></a>
<FONT color="green">221</FONT>                            throws IOException {<a name="line.221"></a>
<FONT color="green">222</FONT>                    //<a name="line.222"></a>
<FONT color="green">223</FONT>            }<a name="line.223"></a>
<FONT color="green">224</FONT>    }<a name="line.224"></a>




























































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